To extract the high-quality DEM in complicated mountain areas,a DEM fusion method for ascending and descending orbit StereoSAR DEMs considering Synthetic Aperture Radar(SAR)echo intensity is proposed.After the analysi...To extract the high-quality DEM in complicated mountain areas,a DEM fusion method for ascending and descending orbit StereoSAR DEMs considering Synthetic Aperture Radar(SAR)echo intensity is proposed.After the analysis for the influence of terrain features and SAR side-looking imaging characteristics on radar echo intensity and DEM accuracy,four Terras AR-X images with the stripmap mode and the 3 m spatial resolution covering a certain area of Maoxian County,Sichuan Province,China,was selected as the experimental area.StereoSAR technology was used to extract the ascending orbit StereoSAR DEM and the descending orbit StereoSAR DEM,respectively,and the corresponding radar echo intensity map was calculated.Then,while comparing the radar echo intensity corresponding to the same point position,DEM fusion was carried out,and the accuracy of DEM before and after the fusion was analyzed with the ground points measured by GNSS-RTK as reference data.Finally,a high-quality DEM with a 3 m spatial resolution in the experimental area was obtained.The DEM accuracy was improved on all slopes,and the mean absolute deviation(MAD)improved to 4.798 m,the standard deviation(SD)improved to 6.087 m and the LE90 improved to 40.48 m.The experimental results indicate that the fusion method of highresolution ascending and descending orbit StereoSAR DEMs considering SAR echo intensity can effectively extract DEM with high accuracy and reliability,which can provide technical support for obtaining highquality terrain information in similar areas.展开更多
Pulmonary arterial hypertension(PAH)is a devastating pulmonary circulation disease lacking high-efficiency therapeutics.The present study aims to decipher the therapeutic mechanism of Rhodiola crenulata,a well-known t...Pulmonary arterial hypertension(PAH)is a devastating pulmonary circulation disease lacking high-efficiency therapeutics.The present study aims to decipher the therapeutic mechanism of Rhodiola crenulata,a well-known traditional chinese medicine with cardiopulmonary protection capacity,on PAH by exploiting functional lipidomics.The rat model with PAH was successfully established for first,following Rhodiola crenulata water extract(RCE)treatment,then analysis of chemical constituents of RCE was performed,additional morphologic,hemodynamic,echocardiographic measurements were examined,further targeted lipidomics assay was performed to identify differential lipidomes,at last accordingly mechanism assay was done by combining qRT-PCR,Western blot and ELISA.Differential lipidomes were identified and characterized to differentiate the rats with PAH from healthy controls,mostly assigned to acylcarnitines,phosphatidylcholines,sphingomyelin associated with the PAH development.Excitingly,RCE administration reversed high level of decadienyl-L-carnitine by the modulation of metabolic enzyme CPT1A in mRNA and protein level in serum and lung in the rats with PAH.Furthermore,RCE was observed to reduce autophagy,confirmed by significantly inhibited PPARγ,LC3B,ATG7 and upregulated p62,and inactivated LKB1-AMPK signal pathway.Notably,we accurately identified the constituents in RCE,and delineated the therapeutic mechansim that RCE ameliorated PAH through inhibition of fatty acid oxidation and autophagy.Altogether,RCE might be a potential therapeutic medicine with multi-targets characteristics to prevent the progression of PAH.This novel findings pave a critical foundation for the use of RCE in the treatment of PAH.展开更多
A robust high temperature sensor probe based on a Ni-coated fiber Bragg grating（FBG） was fabricated by Ni electroplating of femtosecond laser written FBG. The probe can resist high temperature up to 800℃ with a hig...A robust high temperature sensor probe based on a Ni-coated fiber Bragg grating（FBG） was fabricated by Ni electroplating of femtosecond laser written FBG. The probe can resist high temperature up to 800℃ with a high sensitivity of 32.2 pm/℃. It also has a good mechanical strength even after high temperature annealing. The thermal strain of the probe was simulated by the finite element method（FEM）. The Bragg resonant wavelength shift with temperature and its sensitivity change with the thickness of the Ni-coated layer were also calculated.展开更多
基金supported by Study on Early Identification of Landslide Hazards based on Highresolution SAR Image[KJ-2018-13]。
文摘To extract the high-quality DEM in complicated mountain areas,a DEM fusion method for ascending and descending orbit StereoSAR DEMs considering Synthetic Aperture Radar(SAR)echo intensity is proposed.After the analysis for the influence of terrain features and SAR side-looking imaging characteristics on radar echo intensity and DEM accuracy,four Terras AR-X images with the stripmap mode and the 3 m spatial resolution covering a certain area of Maoxian County,Sichuan Province,China,was selected as the experimental area.StereoSAR technology was used to extract the ascending orbit StereoSAR DEM and the descending orbit StereoSAR DEM,respectively,and the corresponding radar echo intensity map was calculated.Then,while comparing the radar echo intensity corresponding to the same point position,DEM fusion was carried out,and the accuracy of DEM before and after the fusion was analyzed with the ground points measured by GNSS-RTK as reference data.Finally,a high-quality DEM with a 3 m spatial resolution in the experimental area was obtained.The DEM accuracy was improved on all slopes,and the mean absolute deviation(MAD)improved to 4.798 m,the standard deviation(SD)improved to 6.087 m and the LE90 improved to 40.48 m.The experimental results indicate that the fusion method of highresolution ascending and descending orbit StereoSAR DEMs considering SAR echo intensity can effectively extract DEM with high accuracy and reliability,which can provide technical support for obtaining highquality terrain information in similar areas.
基金the National Natural Science Foundation of China(No.81302764)the Science and Technology Grant for Excellent Talents of Harbin(No.2017RAXXJ-060).
文摘Pulmonary arterial hypertension(PAH)is a devastating pulmonary circulation disease lacking high-efficiency therapeutics.The present study aims to decipher the therapeutic mechanism of Rhodiola crenulata,a well-known traditional chinese medicine with cardiopulmonary protection capacity,on PAH by exploiting functional lipidomics.The rat model with PAH was successfully established for first,following Rhodiola crenulata water extract(RCE)treatment,then analysis of chemical constituents of RCE was performed,additional morphologic,hemodynamic,echocardiographic measurements were examined,further targeted lipidomics assay was performed to identify differential lipidomes,at last accordingly mechanism assay was done by combining qRT-PCR,Western blot and ELISA.Differential lipidomes were identified and characterized to differentiate the rats with PAH from healthy controls,mostly assigned to acylcarnitines,phosphatidylcholines,sphingomyelin associated with the PAH development.Excitingly,RCE administration reversed high level of decadienyl-L-carnitine by the modulation of metabolic enzyme CPT1A in mRNA and protein level in serum and lung in the rats with PAH.Furthermore,RCE was observed to reduce autophagy,confirmed by significantly inhibited PPARγ,LC3B,ATG7 and upregulated p62,and inactivated LKB1-AMPK signal pathway.Notably,we accurately identified the constituents in RCE,and delineated the therapeutic mechansim that RCE ameliorated PAH through inhibition of fatty acid oxidation and autophagy.Altogether,RCE might be a potential therapeutic medicine with multi-targets characteristics to prevent the progression of PAH.This novel findings pave a critical foundation for the use of RCE in the treatment of PAH.
基金the National Natural Science Foundation of China
文摘A robust high temperature sensor probe based on a Ni-coated fiber Bragg grating（FBG） was fabricated by Ni electroplating of femtosecond laser written FBG. The probe can resist high temperature up to 800℃ with a high sensitivity of 32.2 pm/℃. It also has a good mechanical strength even after high temperature annealing. The thermal strain of the probe was simulated by the finite element method（FEM）. The Bragg resonant wavelength shift with temperature and its sensitivity change with the thickness of the Ni-coated layer were also calculated.
